There ist still a little Bug in Shotcut 19.09.14 and earlier Versions, both on Linux (Linux Mint 19.2) and Windows (Windows 7, 10).
(1) I move the playhead to the startpoint, for example the beginning of the movie.
(2) I press “I” on the keyboard to trim the movie on the timeline. Now the waveform will be displayed wrong. It seems that Shotcut will display it from the beginning of the file, not from the beginning of the trimmed clip.
(3) When i press the “Reset”-button on the properties tab the waveform will be displayed correct.
When I am splitting the clip with “S” it works correct, Shotcut then will rebuild the waveform automatically.